The invention pertains to a wear-resistant member. In particular, the invention concerns a wear member that includes a hard composite member that is securely affixed to at least a portion of a support member. The hard composite comprises a plurality of hard components within a mold wherein an infiltrant alloy that has been infiltrated into the mass of the hard components.
In the past, the temperature at which the infiltrant alloy has been infiltrated into the mass of hard components has been high enough so that the infiltrant alloy had the potential to degrade the hard components upon contact therewith. Thus, there has been a desire to use an infiltrant alloy that has a melting point sufficiently low so as to minimize degradation of the hard components upon contact therewith.
There has also always remained the desire to render the manufacturing process for hard composite members less difficult. It would thus be desirable to use an infiltrant alloy that would ease the manufacturing process for the hard composite.
One example of a hard composite wherein degradation of the hard component was a concern was shown in U.S. Pat. No. 3,149,411 to Smiley et al. In the Smiley et al. patent there was an attempt to minimize the degradation of the cemented carbides by using an alloy that had a melting point between about 1750 degrees Fahrenheit (about 954 degrees Centigrade) and about 3000 degrees Fahrenheit (about 1649 degrees Centigrade). According to the Smiley et al. patent, the alloy also had to contain a metal from Group VIII, Series 4 of the Periodic Table (i.e., iron, cobalt or nickel) and minor amounts of chromium and boron. In the examples (see Cols. 7–8) of the Smiley et al. patent, the typical infiltration temperature ranged between about 2250 degrees Fahrenheit (1232 degrees Centigrade) and about 2600 degrees Fahrenheit (1427 degrees Centigrade).
Another example of a hard composite that had a matrix infiltrated between the interstices of a mass of the hard particles was shown in U.S. Pat. No. 3,175,260 to Bridwell et al. In the Bridwell et al. patent, particles of cemented tungsten carbide or tungsten carbide alloy were heated and the molten matrix metal poured into the mold containing the hard particles. The Bridwell et al. patent mentioned that the melting point of the matrix metal ranged between about 1550 degrees Fahrenheit (843 degrees Centigrade) and 2400 degrees Fahrenheit (1316 degrees Centigrade). The infiltration temperature ranged between about 1750 degrees Fahrenheit (945 degrees Centigrade) and about 2500 degrees Fahrenheit (1371 degrees Centigrade).
U.S. Pat. No. 5,589,268 to Kelley et al. (U.S. Pat. No. 5,733,649 to Kelley et al. was a divisional thereof) pertained to a composite that comprised at least one discrete hard element held by a matrix powder wherein an infiltrant alloy had been infiltrated into the hard components. One suggested infiltrant alloy was a copper-nickel-zinc alloy identified as MACROFIL 65 wherein literature from Belmont Metals, Inc. showed that the melting point was 1100 degrees Centigrade. Another suggested infiltrant alloy was a copper-manganese-nickel-zinc-boron-silicon alloy identified as MACROFIL 53. According to the Kelley et al. patent, the MACROFIL 53 was usually infiltrated at about 2200 degrees Fahrenheit (1204 degrees Centigrade). U.S. Pat. 5,733,664 to Kelley et al. was a continuation-in-part to the '268 Kelley et al. patent. The '664 Kelley et al. patent also disclosed the MACROFIL 53 alloy and the MACROFIL 65 alloy.
Since it is desirable to avoid the degradation of the hard components of a hard composite due to contact with the infiltrant alloy, it would be advantageous to provide a hard composite that utilizes a matrix material that does not degrade (or minimizes the degradation) of the hard components upon contact therewith during the infiltration process.
It is typical that for some applications, the hard composite attaches to a support member to form a wear member. The purpose of the hard composite is to provide wear resistance to the combination of the hard composite and the support member. The support member is intended to provide toughness to the wear member. In these cases, it would be advantageous for the infiltrant alloy and the support member to exhibit compatible properties so as to form a good bond between the hard composite and the support. In this application, it would also be advantageous to maintain the wear resistance properties, as well as the toughness properties, of the hard composite.